The invention relates to an arrangement of grinding modules with grinding tools in track grinders. Such arrangements are used in reprofiling the head of a track profile, in removal of short waves (groovings) as well as in truing long waves in a driving direction. Mostly grinding wheels are used as grinding tools.
Track grinding machines are already known in which a surface pressure of a grinding module is increased or reduced, depending on whether the grinding module moves over a wave trough or over the top of a wave, so that any such waves are leveled, refer to DE-OS 2 037 461. Furthermore, track grinding machines with hydrostatic control are known which, irrespective of the rising of the line or the train resistance, keep to the rate of advance with high precision. A precise positioning of the grinding wheels is essential for the regeneration of the rails, refer to the grinding machine LRR 8-M of the Speno Company. This, however, is particularly problematic with small radii of curvature ( less than 30 m) since there is a comparatively large radial departure of the grinding modules due to common wheel center distances, in particular when both rails are simultaneously ground.
It is an object of the present invention to provide an arrangement of grinding modules in a track grinding machine which permits to exactly involve a radial departure in narrow rail curvature radii ( less than 15 m) without provoking reactive forces, and which allows reprofiling in a reproducible and simple way.
The object is realized by the the present invention providing an arrangement of grinding modules with grinding tools in track grinders, characterized in that each grinding tool has five degrees of freedom of movement, whereby two linear movements are transverse to the rail to be ground, two linear movements are at least approximately vertically to the rail to be ground and one rotational movement is about an axis which is directed in parallel to the rail at the respective grinding site. Thereby it is of no concern whether or not the arrangement has to grind only one rail or to simultaneously grind both rails of a track. In the latter case the arrangement can be used with particular effectiveness. Furthermore, the number of grinding modules, which are comprised to a reprofiling unit in a frame, is insignificant, whereby the frame can be made, for example, of tubular steel.
An advantageous arrangement according to the present invention is obtained when at least one grinding module is at least approximately vertically adjustably seated in a frame and at least approximately horizontally and adjustably seated on a mount via the frame. In the mount, there is provided a housing pivotally arranged about an axis, the axis is at least approximately parallel to a rail to be ground, and in the housing a grinding cylinder is at least approximately displaceable at right angles to the rail to be ground. Preferably a measuring wheel is provided for each grinding module and means for carrying out a relative movement between the grinding module and the measuring wheel. In this way it is possible to include a radial deviation for each grinding module, particularly in narrow curves.
In order to have the measuring wheels always engage via their wheel flanges the rail to which they are associated, each measuring wheel is rotationally seated in a seating mount, which is adjustable, transversely to the rail to be worked on, along a guiding means on the frame, by aid of a servo-drive or a drive means and gearing, preferably a lever system. Preferably, horizontal transversal movement of the mount seated on the frame is carried out by way of a fluid transmission gear in dependence on the transversal movement of the measuring wheel. Thus it is possible to drive into three defined positions (driving the reprofiling unit into operation position, into positioning of the grinding modules, and in pressing the grinding modules to the rail) without the necessity of employing expensive sensing means for each position.
Advantageously, the fluid transmission gear comprises a double cylinder with two opposing pistons in a cylinder chamber of the double cylinder. This design permits using the arrangement according to the invention on different rail gauges, whereby the rail gauge setting range preferably lies between 1000 mm and 1458 mm. Means for blocking the fluid transmission gear are preferably provided for passing complicated curves in the track and points, whereby the fluid transmission gear can be designed as a cylinder-piston-arrangement. The blocking means can be entirely or partially arranged in the vicinity of gearing for the transversal movement of the mount. It is, however, also possible to arrange the blocking means in the vicinity of the measuring wheels of corresponding grinding modules for both rails.
In a further arrangement according to the present invention a plurality of grinding modules can be seated on the frame and corresponding front and rear measuring wheels, considered in the direction of the grinding carriage, can be pivotally joined to the frame for executing movements in vertical directions.
In a further favorable embodiment, provided that the requirements to accuracy are satisfactory for an actual case of application, the grinding modules can be combined in groups on a frame, and each grinding module group is attached to a support which is pivotally seated on the frame in a plane at least approximately parallel to one of the rails. In this case, the measuring wheels are advantageously associated to the grinding module groups. Each of the measuring wheels which are arranged between the grinding module groups is active for the two neighboring grinding module groups which, in the vicinity of the measuring wheels located between them, are pivotally joined to one another about an axis which is arranged substantially at right angles to the rail to be ground.